A wide variety of golf putters are available to address a variety of aspects to help improve putting and aligning the putter during putting.
Golf putters are available that address alignment issues by providing the putter head with graphics such as lines, dots, golf ball sized circles and other shapes for the user to look at as guides.
Golf putters are also available that address line angle with a notch at the top line of a putter. When the horizontal line on the flange sits inside the notch, the user is over the ball.
Golf putters are also available that address dispersion on off-center hits. One way to help decrease dispersion on off-center hits is to increase the Moment Of Inertia (MOI) of the putter head. To accomplish this, the putter usually includes a very large head with added weight in the rear of the putter. This method is effective but the putter is usually not very pleasing to the eye of the golfer (it is considered ugly by golfers).
Others have tried to correct this problem while keeping a traditional head design by adding horizontal lines that vary in width so the energy transfer is variable. End-users have also added inserts to the face of the putter that vary in firmness in an effort to limit dispersion.